Transfer Factors and Potential Ecological Risk Index of Potentially Toxic Metals in Soil, Irrigation Water and Vegetables along Gada River Bank of Jigawa State, Nigeria

Abstract

In recent decades, the concentrations of heavy metals in vegetables are on the increase due to anthropogenic activities. This prompted the current  study to assessed the accumulated potentially toxic metals in the soil, irrigation water, and edible part of selected vegetables along Gada Dam of  Jigawa State, Nigeria, as well as to evaluate the translocation factor, the Monomial Ecological Risk (???? ?? ),and the potential ecological risk index.  The results revealed that the concentrations of these potentially toxic metals are in the order of Mn > Pb > Zn > Ni > Cd > Cu in both water and soil  samples. The transfer factor revealed that, the metals were within the moderate safe level of 1 ≤ ???? ?? < 3for consumption, with cabbage being a  better Zn absorber compared to lettuce. The monomial potential Ecological assessed in these vegetables were within the Low Risk values of ???? ??  ˂ 40 except for Cd in both lettuce and cabbage which are in the range between 80 ≤ ???? ?? ˂ 160, regarded as considerably risk. While Ni in cabbage  is within 40 ≤ ???? ?? ˂ 80 considered as moderate risk. The RI for cabbage is 223.961 and that of lettuce is 172.861, both of which were  deemed very dangerous, according to the grade of Potential Ecological risk posed by toxic metals. All the samples analyzed contained certain levels  of these metals, indicating an evidence of contamination, which may be due to anthropogenic activity.